WO2007004566A1 - Compound, positive resist composition and method for forming resist pattern - Google Patents

Abstract

Disclosed is a positive resist composition which enables to form a resist pattern which is reduced in roughness. Also disclosed is a method for forming a resist pattern. Specifically disclosed is a positive resist composition containing a compound represented by the following general formula (I). (I) (In the formula (I), R11 and R12 independently represent an alkyl group having 1-10 carbon atoms or an aromatic hydrocarbon group, and they may contain a heteroatom in their structures; R21-R24 independently represent a hydrogen atom or an acid-cleavable dissolution inhibiting group, and two of R21-R24 are hydrogen atoms and the other two are acid-cleavable dissolution inhibiting groups; j and k independently represent 0 or an integer of not less than 1 while j + k is not more than 4; and X represents a group represented by the general formula (Ia) or (Ib) below.) (Ia) (Ib) Also specifically disclosed is a method for forming a resist pattern by using such a positive resist composition.

Description

 Specification

 COMPOUND, POSITIVE RESIST COMPOSITION AND METHOD FOR FORMING RESIST PATTERN

 Technical field

 The present invention relates to a compound suitable for a positive resist composition, a positive resist composition, and a resist pattern forming method.

 This application claims priority on July 5, 2005 based on Japanese Patent Application No. 2005-196132 filed in Japan, the contents of which are incorporated herein by reference.

 Background art

 [0002] In recent years, in the manufacture of semiconductor elements and liquid crystal display elements, pattern miniaturization is rapidly progressing due to advances in lithography technology.

 As a technique for miniaturization, the wavelength of an exposure light source is generally shortened. Specifically, the power used in the past, typically ultraviolet rays such as g-line and i-line, has now begun mass production of semiconductor devices using KrF excimer laser and ArF excimer laser. In addition, these excimer lasers have shorter wavelength excimer lasers, electron beams, EUV (

 2

 Extreme ultraviolet rays) and X-rays are being studied.

 As one of the pattern forming materials capable of forming a pattern with a fine dimension, a chemically amplified resist containing a base material component capable of forming a film and an acid generator component that generates an acid upon exposure is known. It has been. Chemically amplified resists are classified into a negative type in which alkali solubility is reduced by exposure and a positive type in which alkali solubility is increased by exposure.

 [0003] Conventionally, polymers have been used as the base component of such chemically amplified resists, such as polyhydroxystyrene (PHS) and resins in which a part of the hydroxyl groups are protected with acid dissociable, dissolution inhibiting groups, etc. PHS resins, (meth) acrylic acid ester-induced copolymers and resins in which a part of the carboxy group is protected with an acid dissociable, dissolution inhibiting group are used.

However, when a pattern is formed using such a pattern forming material, there is a problem that roughness is generated on the upper surface of the pattern and the surface of the side wall. For example, the roughness of the resist pattern side wall surface, that is, the line edge roughness (LER) is added to the hole pattern. This may cause distortion around the hole and variation in line width in the line and space pattern, and may adversely affect the formation of fine semiconductor elements. The problem is more serious as the pattern size is smaller. For this reason, for example, lithography using electron beams or EUV aims to form a fine pattern of several tens of nanometers, so extremely low roughness exceeding the current pattern roughness is required.

 However, polymers generally used as base materials have a large molecular size (average square radius per molecule) of around several nm. In the patterning development process, the dissolution behavior of the resist in the developing solution is usually carried out in units of one molecular component of the base material. Therefore, as long as a polymer is used as the base material component, further reduction in roughness is extremely difficult.

[0004] To solve such problems, a resist using a low-molecular material as a base component has been proposed as a material aiming for extremely low roughness. For example, Patent Documents 1 and 2 propose a low molecular weight material having an alkali-soluble group such as a hydroxyl group and partially or entirely protected with an acid dissociable, dissolution inhibiting group. Such a low molecular weight material is expected to be able to reduce roughness due to its low molecular weight and hence small molecular size.

 Patent Document 1: JP 2002-099088

 Patent Document 2: JP 2002-099089 A

 Disclosure of the invention

 Problems to be solved by the invention

[0005] It is difficult to form a resist pattern with reduced roughness, for example, a pattern finer than 90 nm, at a practically usable level by using a forceful material. For example, there is a problem that the pattern itself cannot be formed (pattern formation ability is low), and even if the pattern can be formed, the roughness is not sufficiently reduced or the shape cannot be sufficiently retained (pattern retention). There are problems such as low performance.

 The present invention has been made in view of the above circumstances, and is suitable for use as a positive resist yarn composition and a resist pattern forming method capable of forming a resist pattern with reduced roughness, and for the positive resist composition. The object is to provide a novel compound.

 Means for solving the problem

[0006] The present inventors pay attention to the state of protection of the phenolic hydroxyl group of the base material component at the molecular level. As a result of extensive studies, it has been found that the above problems can be solved by a compound in which a phenolic hydroxyl group at a specific position of a specific polyvalent phenol compound is protected with a specific number of acid dissociable, dissolution inhibiting groups, The present invention has been completed.

 That is, the first aspect of the present invention is a compound represented by the following general formula (I).

 [0007] [Chemical 1]

[In the formula (I), R ¹¹ and R "each independently represents an alkyl group or aromatic hydrocarbon group having 1 to 10 carbon atoms, and may contain a hetero atom in the structure thereof; R ^{21 to} R ²⁴ are each independently a hydrogen atom or an acid dissociable, dissolution inhibiting group, two of R ^{21 to} R ²⁴ are hydrogen atoms, and the other two are acid dissociable, dissolution inhibiting groups. j and k are each independently an integer of 0 or 1 and j + k is 4 or less; X is a group represented by the following general formula (la) or (lb). Co

[0008] [Chemical 2]

 U a) C I b)

[In the formula (la), R ¹⁸ and R ¹⁹ are each independently an alkyl group having 1 to 10 carbon atoms or an aromatic hydrocarbon group, and may contain a hetero atom in the structure thereof; r, y, z is each independently an integer of 0 or 1 and r + y + z is 4 or less] [0009] The second aspect of the present invention is a positive resist composition comprising a base component (A) whose alkali solubility is increased by the action of an acid, and an acid generator component (B) that generates an acid upon exposure. A thing,

 The positive resist composition is characterized in that the substrate component (A) is a compound (A1) represented by the following general formula (I).

[0010] [Chemical 3]

[In the formula (I), R ¹¹ and R "each independently represents an alkyl group or aromatic hydrocarbon group having 1 to 10 carbon atoms, and may contain a hetero atom in the structure thereof; R ^{21 to} R ²⁴ are each independently a hydrogen atom or an acid dissociable, dissolution inhibiting group, two of R ^{21 to} R ²⁴ are hydrogen atoms, and the other two are acid dissociable, dissolution inhibiting groups. j and k are each independently an integer of 0 or 1 and j + k is 4 or less; X is a group represented by the following general formula (la) or (lb). Co

[0011] [Chemical 4]

 (1 a> (I b)

[In the formula (la), R ¹⁸ and R ¹⁹ are each independently an alkyl group having 1 to 10 carbon atoms or an aromatic hydrocarbon group, and may contain a hetero atom in the structure thereof; r, y, z is each Independently 0 or an integer greater than or equal to 1 and r + y + z is less than 4]

[0012] In a third aspect of the present invention, a step of forming a resist film on a substrate using the positive resist composition of the second aspect, a step of exposing the resist film, and developing the resist film And a resist pattern forming method including a step of forming a resist pattern.

Here, unless otherwise specified, the “alkyl group” in the claims and the specification includes linear, branched and cyclic monovalent saturated hydrocarbon groups.

 “Exposure” is a concept that includes general irradiation of radiation.

 The invention's effect

 [0014] According to the present invention, a positive resist composition and a resist pattern forming method capable of forming a resist pattern with reduced roughness, and a compound suitable for the positive resist composition are provided.

 BEST MODE FOR CARRYING OUT THE INVENTION

 [0015] <Compound>

 The compound of the present invention (hereinafter referred to as compound (A1)) is a compound represented by the above general formula (I).

 In compound (A1), when it is incorporated in a resist composition together with an acid generator component (B) that generates an acid upon exposure, the acid generated from the acid generator component (B) is activated upon exposure. Then, the acid dissociation and dissolution inhibiting group is dissociated, and the entire compound (A1) is changed from alkali-insoluble to alkali-soluble.

In general formula (I), j and k are each independently an integer of 0 or 1 and j + k is 4 or less. j and k are each preferably an integer of 0 to 2, preferably 0 or 1, and most preferably 1.

[0017] R ¹¹ and R ¹² are each independently a linear, branched or cyclic alkyl group having from 10 to 10 carbon atoms, or an aromatic hydrocarbon group.

 The alkyl group is preferably a linear or branched lower alkyl group having from 5 to 5 carbon atoms or a cyclic alkyl group having 5 to 6 carbon atoms.

Examples of the lower alkyl group include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, tert_butyl group, pentyl group, isopentyl group, neopetyl group, and the like. Examples thereof include linear or branched alkyl groups such as an nyl group, and among these, a methyl group is preferable.

 Examples of the cyclic alkyl group include a cyclohexyl group and a cyclopentyl group. The aromatic hydrocarbon group preferably has 6 to 15 carbon atoms such as a phenyl group, a tolyl group, and a xylyl group. , Mesityl group, phenethyl group, naphthyl group, and the like. These alkyl groups or aromatic hydrocarbon groups may contain a hetero atom such as an oxygen atom, a nitrogen atom, or a sulfur atom in the structure.

In compound (A1), the bonding positions of R ¹¹ and R ¹² are not particularly limited, but in terms of excellent effects of the present invention, a carbon atom adjacent to the carbon atom bonded to —OR ^{21 to} —OR ²⁴ (ortho position). It is preferable that R ¹¹ or R ¹² is bonded to at least one of the carbon atoms of the compound (A1—1) represented by the following formula (II): —OR ²¹ — -It is preferable that R ¹¹ is bonded to one of the carbon atoms in the ortho position of the carbon atom to which R ²⁴ is bonded, and R ¹² is bonded to the para position of R ¹¹ .

[0018] X is a group represented by the above general formula (la) or (lb).

In formula (la), R ¹⁸ and R ¹⁹ are each independently an alkyl group having 1 to 10 carbon atoms or an aromatic hydrocarbon group, as in R ¹¹ and R ¹² above, and a hetero atom in the structure thereof May be included.

 The aromatic hydrocarbon group preferably has 6 to 15 carbon atoms, for example, a phenyl group, a tolyl group, a xylyl group, a mesityl group, a phenethyl group, a naphthyl group, and the like r, y, Each z is independently an integer of 0 or 1 and r + y + z is 4 or less.

 X is most preferable because the group represented by the general formula (lb) is easy to synthesize.

[0019] R ²¹ ~R ²⁴ are each independently a hydrogen atom or an acid dissociable, dissolution inhibiting group, R ²¹ ~

Two of R ²⁴ are hydrogen atoms, and the other two are acid dissociable, dissolution inhibiting groups.

The acid dissociation / dissolution-inhibiting group has an alkali dissolution inhibiting property that makes the entire compound (A1) insoluble in alkali before dissociation, and changes the entire compound (A1) to alkali-soluble after dissociation. It is a group. Therefore, in compound (A1), when incorporated in a positive resist composition together with component (B), when the acid generated from component (B) acts upon exposure, the acid dissociation and dissolution inhibiting group dissociates. The whole compound (A1) changes from alkali-insoluble to alkali-soluble.

 [0020] The acid dissociable, dissolution inhibiting group is not particularly limited, and is proposed for hydroxystyrene-based resins, (meth) acrylic acid-based resins, and the like that are used in chemically amplified resist compositions for KrF and ArF. However, it is possible to select and use the force appropriately.

 Specific examples include a tertiary alkyl group, a tertiary alkyloxycarbonyl group, an alkoxycarbonylalkyl group, an alkoxyalkyl group, and a cyclic ether group. Specific examples of the tertiary alkyl group include chain-like tertiary alkyl groups such as tert_butyl group and tert-amyl group, 2_methyl_2-adamantyl group, and 2_ethyl_2-adamantyl group. And tertiary alkyl groups containing an aliphatic polycyclic group.

 Here, “aliphatic” in the present specification and claims is a relative concept with respect to aromatics, and means groups, compounds, etc. that do not have aromaticity. The term “aliphatic cyclic group” means a monocyclic group or polycyclic group having no aromaticity, which may be either saturated or unsaturated, but is usually saturated. preferable.

 Examples of the tertiary alkyl group in the tertiary alkyloxycarbonyl group are the same as those described above. Specific examples of the tertiary alkyloxycarbonyl group include a tert-butyloxycarbonyl group and a tert-amyloxycarbonyl group. Specific examples of the cyclic ether group include a tetrahydrobiranyl group and a tetrahydrofurael group.

 [0021] In the present invention, since it is particularly excellent in the effects of the present invention, it comprises an alkoxycarbonylalkyl group represented by the following general formula (pi) and an alkoxyalkyl group represented by the following general formula (ρ2). It preferably has at least one acid dissociable, dissolution inhibiting group selected from the group.

[0022] [Chemical 5]

[Wherein R ¹ and R ² are each independently a linear, branched or cyclic alkyl group and may contain a hetero atom in the structure; R ³ is a hydrogen atom or a lower alkyl group; N 'is an integer from:! To 3; ]

In the general formula (pi), n ′ is an integer of 1 to 3, and is preferably 1.

[0024] R ¹ is a linear, branched or cyclic alkyl group, and the structure may contain a hetero atom. That is, in the alkyl group as R ¹ , a part or all of the hydrogen atoms may be substituted with a group containing a hetero atom (including the case of the hetero atom itself). It may be substituted with a heteroatom.

 Examples of the hetero atom include an oxygen atom, a sulfur atom, a nitrogen atom, a fluorine atom, etc. The group containing a hetero atom may be a hetero atom itself, or a hetero atom and a carbon atom and / or a hydrogen atom. It may be a group consisting of, for example, an alkoxy group.

 Examples of alkyl groups in which some or all of the hydrogen atoms are substituted with groups containing heteroatoms include, for example, fluorine having from 5 to 5 carbon atoms in which some or all of the hydrogen atoms are substituted with fluorine atoms. A lower alkyl group, a group in which two hydrogen atoms bonded to the same carbon atom are replaced by one oxygen atom (ie, a group having a carbonyl group (C = 〇)), two hydrogens bonded to the same carbon atom And a group in which an atom is substituted with one sulfur atom (that is, a group having a thiocarbonyl group (C = S)).

 Examples of the group in which part of the carbon atom of the alkyl group is substituted with a group containing a hetero atom include, for example, a carbon atom substituted with a nitrogen atom (for example, a branched structure containing —CH— in its structure) Or —CH— is replaced by —NH— in a cyclic alkyl group

twenty two

Group) or an example in which a carbon atom is substituted with an oxygen atom (for example, in a branched or cyclic alkyl group containing —CH— in the structure, —CH— is substituted with —O—) Group) and the like.

[0025] The linear alkyl group as R ¹ preferably has 1 to 5 carbon atoms. Specifically, a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an isobutyl group N-pentyl group, and preferably a methyl group or an ethyl group.

The branched alkyl group as R ¹ preferably has 4 to 10 carbon atoms, more preferably 4 to 8 carbon atoms. Specific examples include an isobutyl group, a tert_butyl group, an isopentyl group, a neopentyl group, a tert_pentyl group, and the like, and preferably a tert_butyl group.

[0026] The cyclic alkyl group as R ¹ preferably has 3 to 20 carbon atoms, more preferably 4 to 14 and most preferably 5 to 12 carbon atoms.

 The structure of the basic ring (basic ring excluding a substituent) in the cyclic alkyl group may be monocyclic or polycyclic. In particular, since the effect of the present invention is excellent, polycyclic is preferable. The basic ring may be a hydrocarbon ring composed of carbon and hydrogen, or may be a heterocyclic ring in which a part of carbon atoms constituting the hydrocarbon ring is substituted with a heteroatom. In the present invention, the basic ring is particularly preferably a hydrocarbon ring. Specific examples of the hydrocarbon ring include monocycloalkane, bicycloalkane, tricycloalkane, and tetracycloalkane. Specific examples include monocycloalkanes such as cyclopentane and cyclohexane, and polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. Among these, adamantane, norbornane, tricyclodecane, and tetracyclododecane are preferable, and adamantane is particularly preferable.

These basic rings may or may not have a substituent on the ring. Examples of the substituent include a lower alkyl group, a fluorine atom, a fluorinated lower alkyl group, an oxygen atom ( = 0). Examples of the lower alkyl group include linear or branched alkyl groups having 1 to 5 carbon atoms such as a methyl group and an ethyl group. When the basic ring has a substituent, the number of substituents is preferably from:! To 3 and more preferably 1. Here, “having a substituent” means that a hydrogen atom bonded to a carbon atom constituting a basic ring is substituted with a substituent. Means that.

Examples of the cyclic alkyl group for R ¹ include groups in which one hydrogen atom has been removed from these basic rings. In R ¹ , it is preferable that the carbon atom to which the oxygen atom adjacent to R ¹ is bonded is one of the carbon atoms constituting the basic ring as described above. In particular, the oxygen atom adjacent to R ¹ The carbon atom bonded to is preferably a tertiary carbon atom bonded to a substituent such as a lower alkyl group, which is excellent in the effects of the present invention and is preferred.

Examples of the acid dissociable, dissolution inhibiting group having a cyclic alkyl group as R ¹ include groups represented by the following formula (P1-1).

[0027] [Chemical 6]

-(P1-1)

[Wherein, R ⁴ is a lower alkyl group, and n is the same as described above. ]

Among these, those represented by the following general formula (Pl — 2) are preferable.

[0029] [Chemical 7]

••• (P1-2)

[Wherein, R ⁴ is a lower alkyl group, and n is the same as described above. ] [0030] The lower alkyl group of R ^{4 is} an alkyl group having 1 to 5 carbon atoms, and specifically includes a methyl group, an ethyl group, a propyl group, an isopropyl group, an nbutyl group, an isobutyl group, a tert- Examples thereof include a lower linear or branched alkyl group such as a butyl group, a pentyl group, an isopentyl group, and a neopentyl group. R ⁴ is more preferably a methyl group that is preferably a methyl group or an ethyl group in terms of industrial availability.

In the formula (p2), examples of R ² include the same as R ¹ described above. Among them, R ² is preferably a linear alkyl group or a cyclic alkyl group.

R ³ is a hydrogen atom or a lower alkyl group. The lower alkyl group for R ^{3 is} an alkyl group having from 5 to 5 carbon atoms, specifically, a methylol group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, Examples include a lower linear or branched alkyl group such as a pentyl group, an isopentyl group, and a neopentyl group. R ³ is more preferably a hydrogen atom or a hydrogen atom, which is preferably a hydrogen atom or a methyl group, in terms of industrial availability.

Examples of the group represented by the formula (p2) wherein R ² is a linear alkyl group include, for example, 1-ethoxyethyl group, ethoxymethyl group, 1-methoxyethyl group, methoxymethylol group, 1-methoxypropyl group, Examples include 1 ethoxypropyl group, 1 n butoxychetyl group, 1 pentafluoroethoxyl group, 1 trifluoromethoxyethyl group, trifluoromethoxymethyl group and the like.

Examples of the group represented by the formula (p2) in which R ² is a cyclic alkyl group include a group represented by the following formula (P2-1).

[0033] [Chemical 8]

(P2-1)

[Wherein R ³ is the same as defined above. ]

Of these, a group represented by the following general formula (P2-2) is preferable.

[0035] [Chemical 9]

••• (P2-2)

[R ³ is the same as above, n ″ is 0, 1 or 2, and W is a hydrogen atom or an oxygen atom of 2 atoms.] [0036] n "is most preferably 0 or 1. Bond between adamantyl group and CHR-0— (CH) —

 3 2 n "position is not particularly limited, but is preferably bonded to the 1- or 2-position of the adamantyl group.

In [0037] Compound (A1), among R ²¹ to R ^24, any two are not limited particularly acid dissociable der Luke, compound (A1), the acid dissociable dissolution inhibiting group It may be a mixture of multiple structural isomers with different bonding positions.

As structural force isomers, those having two acid dissociable, dissolution inhibiting groups on one side as viewed from X in formula (I) (R ²¹ and R ²² are acid dissociable, dissolution inhibiting groups, The other two are hydrogen atoms, and R ²³ and R ²⁴ are acid dissociable, dissolution inhibiting groups and the other two are hydrogen atoms) and X in formula (I) One acid dissociable, dissolution inhibiting group exists on both sides (R ²¹ and R ²³ are acid dissociable, dissolution inhibiting groups, the other two are hydrogen atoms, R ²² and R ²⁴ are acid dissociated The other two are hydrogen atoms, etc.).

 As the compound (A1), a compound (A1-1) represented by the following formula (II) is particularly preferable.

 [0039] [Chemical 10]

[In the formula (II), R ″ to R ¹² , R ^{21 to} R ²⁴ and X are the same as above.]

 Compound (A1) can be produced, for example, as follows.

First, for the polyvalent phenolic compound (a) in which R ^{21 to} R ²⁴ in formula (I) are all hydrogen atoms, the hydrogen atom of the phenolic hydroxyl group is inhibited by acid dissociable dissolution by a well-known method. Substituted with a group (for example, the polyvalent phenol compound (a) and the formula X—Y , Halogen atoms such as chlorine atoms, and Y represents an acid dissociable, dissolution inhibiting group. To obtain a mixture of compounds in which part or all of the hydrogen atoms of the phenolic hydroxyl group are substituted with acid dissociable, dissolution inhibiting groups.

Thereafter, other than compounds in which two of R ^{21 to} R ²⁴ are substituted with an acid dissociable, dissolution inhibiting group are purified by liquid chromatography or the like by a known method such as liquid chromatography or molecular weight fractionation. It can be obtained by removing or the like.

 The polyhydric phenol compound (a) can be synthesized, for example, by dissolving a bissalicylaldehyde derivative and a phenol derivative (about 4 equivalents relative to the bissalicylaldehyde derivative) in an organic solvent and then reacting them under acidic conditions. Can do.

 Here, the polyvalent phenol compound (a) preferably has a molecular weight of 300 to 2500, more preferably 450 to 1500, and still more preferably 500 to 1200. When the molecular weight force S is lower than the upper limit, when the compound (A1) is used in the resist composition, the roughness is reduced, the pattern shape is further improved, and the resolution is also improved. In addition, when it is at least the lower limit value, a resist pattern having a good profile shape can be formed.

[0042] The polyvalent phenol compound (a) is a material capable of forming an amorphous film by a spin coating method. Here, the amorphous film means an optically transparent film that does not crystallize. The spin coating method is one of the commonly used thin film formation methods. The polyphenol compound ( _a ) is _a material that can form an amorphous film by the spin coating method. It can be determined by whether or not the coating film formed by spin coating on the wafer is completely transparent. More specifically, for example, it can be determined as follows. First, for the polyhydric phenol material, a solvent generally used as a resist solvent is used, for example, a mixed solvent of lactic acid ethyl Z propylene glycol monomethyl etherate = 40Z60 (mass ratio) (hereinafter referred to as ΕΜ). Are mixed so that the concentration of the polyvalent phenolic material is 14% by mass, and is subjected to ultrasonic treatment (dissolution treatment) using an ultrasonic cleaner to dissolve the solution. Spin coated at 1500rpm, and optionally dry beta (PAB, Post Applied Bake) is applied at 110 ° C for 90 seconds. In this state, an amorphous film is formed depending on whether it is transparent or not. Whether or not Confirm. A cloudy film that is not transparent is not an amorphous film. In the present invention, the polyphenol compound (a) preferably has good stability of the amorphous film formed as described above. For example, after the PAB, the polyphenol compound (a) is allowed to stand in a room temperature environment for 2 weeks. It is preferable that the amorphous state is maintained even after the treatment.

[0043] The compound (A1) of the present invention is a polyhydric phenol compound (a) in which R ^{21 to} R ²⁴ in the formula (I) are all hydrogen atoms. In this compound, _{two of the} four phenolic hydroxyl groups are protected with an acid dissociable, dissolution inhibiting group, and the number of protection is _two .

 Here, the “protection number” means the number of phenolic hydroxyl groups protected with an acid dissociable, dissolution inhibiting group in the compound (A1).

 For example, the protection number (%) of the compound (A1) is measured by NMR (nuclear magnetic resonance spectrum) such as proton-NMR and carbon NMR, and the value and the structure of the polyvalent phenol compound (a) are measured. Can be sought.

 Here, the “protection rate” means the number of phenolic hydroxyl groups protected with an acid dissociable, dissolution inhibiting group (that is, the number of protections) in compound (A1) and the protected hydroxyl group, phenolic hydroxyl group. It means the ratio (mol%) of the protection number to the total of the numbers.

In the present invention, a resist pattern with reduced roughness can be formed by using a powerful compound (A1).

The reason is considered as follows. As described above, the compound (A1) has a structure in which two of the four specific phenolic hydroxyl groups of the polyhydric phenol compound having a specific structure are protected with an acid dissociable, dissolution inhibiting group. During the synthesis reaction, multiple molecules with different numbers of protection are usually generated. That is, what is obtained after the synthesis is usually a mixture containing a plurality of molecules having different protection numbers in addition to the compound (A1). Therefore, there are variations in the number of acid dissociable, dissolution-inhibiting groups from molecule to molecule, and there are differences in properties from molecule to molecule, such as differences in alkali solubility, which can be obtained by using a resist that uses force and a mixture. The resist film is assumed to have non-uniform properties such as the distribution of various components in the film, alkali solubility, thermal properties (Tg (glass transition point), etc.), and the roughness is thereby deteriorated. Is done. On the other hand, in the present invention, by using a compound having two protected hydroxyl groups and a protection number of 2 alone, there is no difference in properties for each molecule, for example, no difference in alkali solubility. It is estimated that a resist pattern with reduced roughness can be formed.

[0045] << Positive Resist Composition >>

 The positive resist composition of the present invention comprises a base component (A) (hereinafter sometimes referred to as component (A)) whose alkali solubility is increased by the action of an acid, and an acid generator component that generates an acid upon exposure. Containing the component (B) (hereinafter also referred to as component (B)).

 In the component (A), when the acid generated from the component (B) acts upon exposure, the entire component (A) changes from alkali-insoluble to alkali-soluble. Therefore, when a resist film made of the positive resist composition is selectively exposed or heated after exposure in addition to exposure in the formation of a resist pattern, the exposed portion becomes alkali-soluble while the unexposed portion becomes alkaline. Since it remains insoluble and does not change, a positive resist pattern can be formed by alkali development.

[0046] <(A) component>

 In the positive resist composition of the present invention, the component (A) needs to be the above-described compound (A1) of the present invention. Here, that the component (A) is the compound (A1) means that the component (A) does not contain a base material component whose alkali solubility is increased by the action of an acid other than the compound (A1). To do.

 In the component (A), the compound (A1) may be used alone or in combination of two or more.

[0047] The content of the component (A) in the positive resist composition of the present invention may be adjusted according to the thickness of the resist film to be formed.

<Component (B)> The component (B) is not particularly limited, and those that have been proposed as acid generators for chemically amplified resists can be used. Examples of such acid generators include onium salt-based acid generators such as odonium salts and sulfonium salts, oxime sulfonate-based acid generators ij, bisalkyl or bisarylsulfonyldiazomethanes, Diazomethane acid generators such as poly (bissulfonyl) diazomethanes, nitrobenzyl sulfonate acid generators, iminosulfonate acid generators, disulfone acid generators Various things such as agents are known.

 [0049] Examples of the onium salt-based acid generator include an acid generator represented by the following general formula (b-0).

[0050] [Chemical 11]

[Wherein, ¹ represents a linear, branched, or cyclic alkyl group, or a linear, branched, or cyclic fluorinated alkyl group; R ⁵² represents a hydrogen atom, a hydroxyl group, a halogen atom, or a linear chain. Or a branched alkyl group, a linear or branched haloalkyl group

Or R ⁵³ is an optionally substituted aryl group; u is an integer from ι to 3. ]

In the general formula (b_0), R ⁵¹ represents a linear, branched or cyclic alkyl group, or a linear, branched or cyclic fluorinated alkyl group.

 The linear or branched alkyl group preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and still more preferably 1 to 4 carbon atoms. . The cyclic alkyl group is most preferably 4 to 12 carbon atoms, preferably 5 to 10 carbon atoms, and more preferably 6 to 10 carbon atoms.

 The fluorinated alkyl group is most preferably 1 to 4 carbon atoms, preferably 1 to 10 carbon atoms, more preferably 1 to 4 carbon atoms. Also. The fluorination rate of the alkyl group (the ratio of the number of substituted fluorine atoms to the total number of hydrogen atoms in the alkyl group) is preferably 10 to 100%, more preferably 50 to 100%. All hydrogen atoms substituted with fluorine atoms are preferred because the strength of the acid increases.

R ⁵¹ is most preferably a linear alkyl group or a fluorinated alkyl group.

[0052] R ⁵² represents a hydrogen atom, a hydroxyl group, a halogen atom, a linear, branched or cyclic alkyl. Group, a linear or branched alkyl halide group, or a linear or branched ananoloxy group.

In R ⁵² , examples of the halogen atom include a fluorine atom, a bromine atom, a chlorine atom, and an iodine atom, and a fluorine atom is preferable.

In R ⁵² , when the alkyl group is linear or branched, its carbon number is preferably 1 to 5, in particular:! To 4, more preferably 1 to 3, and . In R ⁵² , when the alkyl group is a cyclic alkyl group, the carbon number thereof is preferably 4 to: 12, more preferably 5 to 10 carbon atoms, and more preferably 6 to 6 carbon atoms. : 10 is most preferable. In R ⁵² , the halogenated alkyl group is a group in which part or all of the hydrogen atoms in the alkyl group are substituted with halogen atoms. Examples of the alkyl group here are the same as the “alkyl group” in R ⁵² . Examples of the halogen atom to be substituted include the same as those described above for the “halogen atom”. In the halogenated alkyl group, it is desirable that 50 to 100% of the total number of hydrogen atoms are substituted with halogen atoms, and it is more preferable that all are substituted.

In R ⁵² , the alkoxy group is linear or branched, and the carbon number thereof is preferably 1 to 5, in particular:! To 4, more preferably 1 to 3.

Among these, R ⁵² is preferably a hydrogen atom.

[0053] R ⁵³ is an optionally substituted aryl group, preferably having 6 to 15 carbon atoms, and the structure of the basic ring (matrix ring) excluding the substituent is a naphthyl group A phenyl group and an anthracenyl group. From the viewpoint of the effect of the present invention and the absorption of exposure light such as an ArF excimer laser, a phenyl group is desirable.

 Examples of the substituent include a hydroxyl group and a lower alkyl group (straight chain or branched chain, preferably having 5 or less carbon atoms, particularly preferably a methyl group).

As the aryl group for R ⁵³ , those having no substituent are more preferable.

 u is an integer from:! to 3 and is preferably 2 or 3, especially preferably 3.

[0054] Preferable examples of the acid generator represented by the general formula (b_0) include those represented by the following chemical formula (b_0_0). [0055] [Chemical 12]

 ••• (b-0-0)

 [0056] Among them, a compound represented by the following chemical formula (b-0-1) is preferred.

[0057] [Chemical 13]

CP ₃ SO

[0058] The acid generator represented by the general formula (b_0) can be used alone or in combination of two or more.

 [0059] Examples of other acid salt-based acid generators represented by the general formula (b_0) include compounds represented by the following general formula (b-1) or (b-2) .

[0060] [Chemical 14]

[Wherein “˜” and R ⁵ “˜R ^e ” independently represent an aryl group or an alkyl group. R ⁴ ″ represents a linear, branched or cyclic alkyl group or a fluorinated alkyl group; at least one of R ¹ ″ to R ³ ″ represents an aryl group, and R ⁵ ″ to R ⁶ ″ At least one of them represents an aryl group.]

In the formula (b_l), 1 ^ "to 1 ³ " each independently represents an aryl group or an alkyl group. At least one of R ¹ "to R ³ " represents an aryl group. It is preferred that 2 or more of 1 ^ "to 1 ³ " are aryl groups. Most preferably, all of "~" are aryl groups.

The Ariru groups R1 "to R ^3", particularly limited Nag example, an Ari Honoré group having 6 to 20 carbon atoms, said Ariru groups, part or all alkyl groups of the hydrogen atom, § alkoxy It may or may not be substituted with a group, a halogen atom or the like. The aryl group is preferably an aryl group having 6 to 10 carbon atoms because it can be synthesized at low cost. Specific examples include a phenyl group and a naphthyl group.

 Examples of the alkyl group that may be substituted with a hydrogen atom in the aryl group include a methylol group, an ethynyl group, a propyl group, an n-butyl group, and a tert-butyl group. Les is most preferred to be.

 As the alkoxy group that may be substituted with a hydrogen atom of the aryl group, a methoxy group and an ethoxy group are preferred, with an alkoxy group having 1 to 5 carbon atoms being preferred.

 The halogen atom that may be substituted for the hydrogen atom of the aryl group is preferably a fluorine atom.

 The alkyl group of “˜” is not particularly limited, for example, a linear or branched alkyl group having 1 to 10 carbon atoms or 4 to 15 carbon atoms, preferably 4 to 10 carbon atoms, more preferably 6 to 1 carbon atoms. 0 cyclic alkyl group and the like can be mentioned. From the viewpoint of excellent resolution, the carbon number is preferably! Specifically, methyl group, ethyl group, n-propyl group, isopropyl group, n_butyl group, isobutyl group, n_pentyl group, cyclopentyl group, hexyl group, cyclohexyl group, nonyl group, decanyl group A methyl group can be mentioned as a preferred product because it is excellent in resolution and can be synthesized at low cost.

 Of these, 1 ^ "to" are most preferably phenyl groups.

[0062] R ⁴ "represents a linear, branched or cyclic alkyl group or fluorinated alkyl group.

The linear alkyl group preferably has 1 to 10 carbon atoms, preferably 8 to 8 carbon atoms. Most preferably, it is 1 to 4 carbon atoms.

The cyclic alkyl group is a cyclic group as indicated by R ¹ ″, preferably having 4 to 15 carbon atoms, and more preferably having 4 to 10 carbon atoms. Most preferably, it is 6 to 10 carbon atoms.

 Most preferably, the fluorinated alkyl group has 1 to 10 carbon atoms, preferably 8 to 8 carbon atoms, and more preferably 1 to 4 carbon atoms. Also. The fluorination rate of the fluorinated alkyl group (ratio of fluorine atoms in the alkyl group) is preferably 10 to 100%, more preferably 50 to 100%. In particular, all hydrogen atoms are fluorine atoms. The substituted one is preferable because the strength of the acid is increased.

R ⁴ ″ is most preferably a linear or cyclic alkyl group or a fluorinated alkyl group.

In the formula (b — 2), R ⁵ ″ and R ⁶ ″ each independently represent an aryl group or an alkyl group. At least one of R ⁵ "and R ⁶ " represents an aryl group. It is preferred that all of R ⁵ "and R ⁶ " are aryl groups.

Examples of the aryl group of R ⁵ "and R ⁶ " include the same aryl groups as "~".

Examples of the alkyl group for R ⁵ ″ and R ⁶ ″ include the same alkyl groups as 1 ^ ″ to 1 ³ ″.

Among these, it is most preferable that R ⁵ ″ and R ⁶ ″ are all phenyl groups.

Formula (b-2) R ⁴ in "The R ⁴ in the formula (b-1)" are the same as those for.

Specific examples of the onium salt acid generators represented by the formulas (b-1) and (b-2) include trifluoromethanesulfonate, nonafluorobutanesulfonate, bis (4_tert _Butylphenol) trifluoromethane sulfonate or nonafluorobutane sulfonate, trifluoromethane sulfonate, heptafluoropropane sulfonate or nonafluorobutans sulfonate, tri ( 4-methylphenolino) sulfurium trifluoromethanesulfonate, heptafluoropropane sulfonate or nonafluorobutane sulfonate, dimethyl (4-hydroxynaphthinole) sulfurium trifluoromethanesulfonate, So Of heptafluoropropane sulfonate or nonafluorobutane sulfonate thereof, trifluoromethane sulfonate of monophenyl dimethyl sulfonate, heptafluoropropane sulfonate or nonafluorobutane sulfonate thereof, diphenyl monomethyl sulfone Trifluoromethane sulfonate, its heptafluoropropanes norephonate or its nonafluorobutane sulfonate, (4-methylphenenole) diphenol Noresnorephonium trifanolomethane senorephonate, its heptafluoronoleo Lopropane sulphonate or its nonafluorobutane sulphonate, (4-methoxyphenyl) diphenyl snorefonium trifonoleolomethane sulphonate, its heptafunole propanesno Phonate or its nonafluorobutane sulfonate, tri (4_tert-butynole) phenylsulfone Phosphonium trifluoromethanesulfonate, its heptafluoropropane sulfonate or its nonafluorobutane sulfonate, diphenyl (1- (4-methoxy) ) Naphthyl) Snolephonium trifonoleolomethane sulphonate, heptafunole propane sulphonate or its nonafluorobutane sulfonate. Further, onium salts in which the anion portion of these onium salts is replaced with methanesulfonate, n-propanesulfonate, n-butanesulfonate, or n-octanesulfonate can also be used.

 [0065] Further, in the general formula (b-1) or (b-2), an anion salt system in which the anion part is replaced with an anion part represented by the following general formula (b-3) or (b-4) An acid generator can also be used (the cation moiety is the same as (b-1) or (b-2)).

 [0066] [Chemical 15]

[Wherein X "represents a C 2-6 alkylene group in which at least one hydrogen atom is replaced by a fluorine atom; Υ", Ζ "each independently represents at least one hydrogen atom is fluorine. Represents an alkyl group substituted with atoms:! -10.]

[0067] X "is a linear or branched alkylene group in which at least one hydrogen atom is substituted with a fluorine atom, and the alkylene group has 2 to 6 carbon atoms, preferably 3 to 3 carbon atoms. Five Most preferably, it has 3 carbon atoms.

 Υ "and Ζ" are each independently a linear or branched alkyl group in which at least one hydrogen atom is substituted with a fluorine atom, and the alkyl group has: Has 1 to 7 carbon atoms, more preferably 1 to 3 carbon atoms.

 The carbon number of the alkylene group of X ″ or the carbon number of the alkyl group of “ア ル キ ル” and “Ζ” is preferably as small as possible within the range of the above-mentioned carbon number for reasons such as good solubility in a resist solvent.

 In addition, in the alkylene group of X "or the alkyl group of Υ" and Ζ ", the greater the number of hydrogen atoms substituted with fluorine atoms, the stronger the acid strength and the higher the energy of 200 nm or less. The ratio of fluorine atoms in the alkylene group or alkyl group, that is, the fluorination rate is preferably 70 to 100%, more preferably 90 to 100. And most preferably a perfluoroalkylene group or a perfluoroalkyl group in which all hydrogen atoms are substituted with fluorine atoms.

 [0068] In the present invention, the oxime sulfonate acid generator is a compound having at least one group represented by the following general formula (式 -1), and generates an acid upon irradiation with radiation. It is what has. Such oxime sulfonate acid generators are widely used for chemically amplified resist compositions, and can be arbitrarily selected and used.

[0069] [Chemical 16]

(In the formula (B-1), R ³¹ and R ³² each independently represents an organic group.)

 [0070] In the present invention, an organic group is a group containing a carbon atom, and an atom other than a carbon atom (for example, a hydrogen atom, an oxygen atom, a nitrogen atom, a sulfur atom, a halogen atom (a fluorine atom, a chlorine atom, etc.)). Etc.).

The organic group for R ³¹ is preferably a linear, branched or cyclic alkyl group or aryl group. These alkyl groups and aryl groups may have a substituent. The substituent is not particularly limited, for example, a fluorine atom, a straight chain, branched or cyclic group having from 6 to 6 carbon atoms. An alkyl group etc. are mentioned. Here, “having a substituent” means that part or all of the hydrogen atoms of the alkyl group or aryl group are substituted with a substituent.

 As the alkyl group, carbon number:! -20 is preferable carbon number:!-10 is more preferable carbon number 1-8 is more preferable carbon number 1-6 is particularly preferable carbon number 1- 4 is most preferred. As the alkyl group, a partially or completely halogenated alkyl group (hereinafter sometimes referred to as a halogenated alkyl group) is particularly preferable. The partially halogenated alkyl group means an alkyl group in which a part of hydrogen atoms is substituted with a halogen atom, and the fully halogenated alkyl group means that all the hydrogen atoms are halogen atoms. It means an alkyl group substituted by. Examples of the halogen atom include a fluorine atom, a chlorine atom, an fluorine atom, and an iodine atom, and a fluorine atom is particularly preferable. That is, the halogenated alkyl group is preferably a fluorinated alkyl group.

 The aryl group preferably has 4 to 20 carbon atoms, preferably 4 to 10 carbon atoms, and more preferably 6 to 10 carbon atoms. As the aryl group, a partially or completely halogenated aryl group is particularly preferable. A partially halogenated aryl group means an aryl group in which a part of hydrogen atoms is replaced with a halogen atom, and a fully halogenated aryl group means that all hydrogen atoms are halogen atoms. An aryl group substituted with an atom.

R ³¹ is particularly preferably an alkyl group having 1 to 4 carbon atoms having no substituent or a fluorinated alkyl group having 1 to 4 carbon atoms.

As the organic group for R ³² , a linear, branched or cyclic alkyl group, aryl group or cyan group is preferable. As the alkyl group and aryleno group for R ^32, the same alkyl groups and aryl groups as those described above for R ³¹ can be used.

R ³² is particularly preferably a cyano group, an alkyl group having 1 to 8 carbon atoms having no substituent, or a fluorinated alkyl group having 1 to 8 carbon atoms.

 [0072] More preferable examples of the oxime sulfonate-based acid generator include compounds represented by the following general formula (B-2) or (B-3).

[0073] [Chemical 17]

,,, Β2 [In the formula (B-2), R ^dd represents a cyano group, an alkyl group having no substituent, or a halogenated alkyl group. R ³⁴ is an aryl group. R ³⁵ represents an alkyl group having no substituent or a halogenated alkyl group. ]

[Chemical 18]

■ (B-3)

[In the formula (B_3), R ^dt> represents a cyano group, an alkyl group having no substituent, or a halogenated alkyl group. R ³⁷ is a divalent or trivalent aromatic hydrocarbon group. R ³⁸ is an alkyl group having no substituent or a halogenated alkyl group. p is 2 or 3. ]

[0075] In the general formula (B_ 2), alkyl or halogenated alkyl group which includes no substituent R ³³ is 1 to carbon atoms: preferably from 10 tool 1 to 8 carbon atoms More preferred C 1-6 is most preferred.

R ³³ is more preferably a fluorinated alkyl group, preferably a halogenated alkyl group.

The fluorinated alkyl group for R ³³ preferably has 50% or more of the hydrogen atom of the alkyl group, more preferably 70% or more, and even more preferably 90% or more. .

[0076] The aryl group of R ³⁴ includes a hydrogen atom from an aromatic hydrocarbon ring such as a phenyl group, a biphenyl group, a fluorenyl group, a naphthyl group, an anthracyl group, a phenanthryl group, and the like. And a heteroaryl group in which a part of the carbon atoms constituting the ring of these groups is substituted with a heteroatom such as an oxygen atom, a sulfur atom or a nitrogen atom. Among these, a fluorenyl group is preferable.

The aryl group of R ³⁴ may have a substituent such as an alkyl group having 1 to 10 carbon atoms, a halogenated alkyl group, or an alkoxy group. The alkyl group or halogenated alkyl group in the substituent preferably has 1 to 8 carbon atoms, more preferably 1 to 4 carbon atoms.

. The halogenated alkyl group is preferably a fluorinated alkyl group.

[0077] The alkyl group or halogenated alkyl group having no substituent of R ³⁵ has 1 to A carbon number of 1 to 6 which is preferably 10 is most preferable, and a carbon number of 1 to 6 is more preferable.

R ³⁵ is preferably a halogenated alkyl group, more preferably a fluorinated alkyl group, and more preferably a partially fluorinated alkyl group.

The fluorinated alkyl group in R ³⁵ preferably has a hydrogen atom of the alkyl group of 50% or more fluorinated, more preferably 70% or more, and still more preferably 90% or more. This is preferable because the strength of the generated acid is increased. Most preferably, it is a fully fluorinated alkyl group in which a hydrogen atom is 100% fluorine-substituted.

[0078] In the general formula (B _ 3), the alkyl group or halogenated alkyl group which includes no substituent of R ^36, Les such no substituent of the R ^33, an alkyl group or a halogen Kaa The thing similar to a rualkyl group is mentioned.

Examples of the divalent or trivalent aromatic hydrocarbon group for R ³⁷ include groups obtained by further removing one or two hydrogen atoms from the aryl group for R ³⁴ .

Les such no substituent of R ^38, the alkyl group or Harogeni spoon alkyl group, the same alkyl group or halogenated alkyl group which includes no substituent of the ⁵ like et be. p is preferably 2.

[0079] Specific examples of oxime sulfonate acid generators include α (p-toluenesulfonyloxyimino) benzylcyanide, α (ρ chlorobenzenesulfonyloxyimino) —benzylcyanide, α- (4-nitrobenzene Sulfonyloxyimino) monobenzylcyanide, α (4-12 tallow 2 trifluoromethylbenzenesulfonyloxyximino) benzylcyanide, α- (benzenesulfonyloxyimino) -4-chlorobenzoylcyanide , Α (Benzenesulfonyloxyimino) -1,2,4-dichlorobenzylcyanide, α- (Benzenesulfonyloxyimino) -1,2,6-dichlorobenzylcyanide, Hiichi (Benzenesulfonyloxyimino) _ 4-Methoxybenzylcyanide, bis- (2-chlorobenzenesulfonyloxymino) _4-Methoxybenz Cyanide, arsenic - (benzenesulfonyl two Ruokishiimino) - Cheng - 2 I Rua Seto nitrile, a - (4-dodecyl benzene Niruokishiimino) - benzyl cyanide, _a - [(p-toluenesulfonyl O key Consequences amino) - 4 —Methoxyphenyl] acetonitrile, 一 [[dodecylbenzenesulfonyloxyimino) _ 4-methoxyphenyl] acetonitrile, α-(tosyloximino) _4 _Chelicirsia Nido, α (methylsulfonyloxyimino) 1-cyclopentenylacetonitrile, (methylsulfonyloxyimino) 1-cyclohexenylacetonitrile, a (methylsulfonyloxyimino) 1-cycloheptenylacetonitrile , A (methylsulfonyloxymino) 1 1-cyclootaturacetonitrile, _a- (trifluoromethylsulfonyloxymino) _ 1-cyclopentenylrucetonitrile, _a- (trifluoromethylsulfonyloxy) Mino) -Cyclohexylacetonitrile,-(Ethylsulfonyloxymino) -Ethylacetonitrile, _α- (Propylsulfonyloxymino) -Propylacetonitrile, _α- (Cyclohexylsulfonyloxy) Mino) monocyclopentylacetonitrile, a-(cyclohexylsulfur Nyloxymino) monocyclohexylacetonitrile,-(cyclohexylsulfonyloxyximino) _ 1-cyclopentenylrucetonitrile, a- (ethylsulfonyloxyximino) _ 1-cyclopentenyllucetonitrile, ichiichi ( Isopropylsulfonyloxymino) _ 1-Cyclopentenylacetonitrile, bis- (n-butylsulfonyloxymino) 1-cyclopentenylacetonitrile, _a (Ethylsulfonyloxymino) 1-Cyclohexenylacetonitrile , _a (isopropylsulfanyl Honi Ruo key Consequences amino) Single 1 Shikuro to hexenyl Rua Seto nitrile, a one (n Buchirusuruhoni Ruokishiimino) 1 hexenyl Rua Seto nitrile to Shikuro, a (methylsulfonyl O carboxymethyl imino) phenylene Ruasetonitoriru, a (methyl Sulfonyximino ) P methoxyphenylacetonitrile, a (trifluoromethylsulfonyloximino) phenylacetonitrile, _a (trifluoromethylsulfonyloxymino) p methoxyphenylacetonitrile, a (ethylsulfonyloxyximino) ) -P methoxyphenylacetonitrile, α- (propylsulfonyloxyimino) p methylphenylacetonitrile,-(methylsulfonyloxyimino) _p_bromophenylacetonitrile, and the like.

 Moreover, the compound (compound group (i)) represented by the following chemical formula is mentioned.

[Chemical 19]

 …)

 [0081] Examples of preferable compounds (compound groups (ii) and (iii)) among the compounds represented by the general formula (B-2) or (B-3) are shown below.

[0082] [Chemical 20]

(ii)

~ (Iii)

 [0084] Among the above exemplified compounds, the following four compounds ((iv) to (vii)) are preferable.

[0085] [Chemical 22]

(iv) [0086] [Chemical 23]

-C = "HQSOf 《CH2 ₃ GH ₃

 [0087] [Chemical 24]

 [0088] Among diazomethane acid generators, specific examples of bisalkyl or bisarylsulfonyldiazomethanes include bis (isopropylsulfonyl) diazomethane, bis (p-toluenesulfonyl) diazomethane, bis (1 , 1_dimethylethylsulfonyl) diazomethane, bis (cyclohexylsulfoninole) diazomethane, bis (2,4-dimethylphenylsulfonyl) diazomethane, and the like.

 Poly (bissulfonyl) diazomethanes include, for example, 1,3-bis (phenylsulfonyldiazomethylsulfonole) propan (A = having the structure represented by the following formulas (viii) and (ix): 3), 1,4-bis (phenylsulfonyldiazomethylsulfoninole) butane (when A = 4), 1,6-bis (phenylsulfonyldiazomethylsulfoninole) hexane (When A = 6), 1,10-bis (phenylsulfonyldiazomethylsulfoninole) decane (when A = 10), 1,2-bis (cyclohexylsulfonyldiazomethylsulfoninole) Ethane (when B = 2), 1, 3-bis (cyclohexylsulfonyl diazomethylsulfonyl) Propane (when B = 3), 1, 6-bis (cyclohexylsulfonyl diazomethyl sulfone) Nyl) hexane (when B = 6), 1, 10 —Bis (cyclohexylsulfonyldiazomethylsulfonyl) decane (when B = 10).

[0089] [Chemical 25]

 [0090] As the component (B), one type of these acid generators may be used alone, or two or more types may be used in combination.

 In the present invention, it is particularly preferable to use an onium salt having a fluorinated alkyl sulfonate ion as an ion as the component (B).

 The content of the component (B) in the positive resist composition of the present invention is preferably 0.5 to 30 parts by mass, more preferably 15 to 15 parts by mass with respect to 100 parts by mass of the component (A). By making it in the above range, pattern formation is sufficiently performed. In addition, a uniform solution is obtained, and storage stability is improved, which is preferable.

[0091] <Optional component>

 The positive resist composition of the present invention is further optional in order to improve the resist pattern shape, post exposure stability of the latent image formed by the pattern-wise exposure or the resist layer, etc. As the component, a nitrogen-containing organic compound (D) (hereinafter referred to as component (D)) can be blended.

Since a wide variety of components (D) have already been proposed, any known one can be used. For example, n-hexylamine, n-ptylamine, n-octylamine, n-nonylamine, n- Monoalkylamines such as decylamine; dialkylamines such as jetylamine, di-n-propylamine, di-n-ptylamine, di-n-octylamine, dicyclohexylamine; trimethylamine, triethylamine, tri-n-propylamine, tri-n —Trialkylamines such as butyramine, tri_n—hexylamine, tri_n—pentylamine, tri-n-heptylamine, tri_n—octylamine, tri_n—nonylamine, tri_n—de-force nylamine, tri-n-dodecylamine; Diethanolamine, bird Examples thereof include alkyl alcohol amines such as ethanolamine, diisopropanolamine, triisopropanolamine, di-n-octanolamine, and tri-n-octanolamine. Of these, tri-n-octylamine is most preferred, with secondary aliphatic amines being preferred for tertiary aliphatic amines, and trialkylamines having 5 to 10 carbon atoms being more preferred.

 These can be used alone or in combination of two or more.

Component (D) is usually used in the range of 0.01 to 5.0 parts by mass per 100 parts by mass of component (A).

 [0092] In the positive resist composition of the present invention, as an optional component for the purpose of preventing sensitivity deterioration due to the blending of the component (D) and improving the resist pattern shape, stability with time, etc. An organic carboxylic acid or phosphorus oxo acid or a derivative thereof (E) (hereinafter referred to as component (E)) can be contained. In addition, the component (D) and the component (E) can be used together, or one kind of force can be used.

 As the organic carboxylic acid, for example, malonic acid, citrate, malic acid, succinic acid, benzoic acid, salicylic acid and the like are suitable. Phosphorus oxoacids or derivatives thereof include phosphoric acid, phosphoric acid di-n-butyl ester, phosphoric acid diphenyl ester and other phosphoric acid or derivatives such as these esters, phosphonic acid, phosphonic acid dimethyl ester, phosphonic acid Acids phosphonic acids such as n-butyl ester, phenylphosphonic acid, diphenyl ester of phosphonic acid, dibenzyl ester of phosphonic acid and derivatives thereof, phosphinic acids such as phosphinic acid, phenylphosphinic acid and esters thereof And phosphonic acid is particularly preferable.

 Component (E) is used in a proportion of 0.01 to 5.0 parts by mass per 100 parts by mass of component (A).

[0093] The positive resist composition of the present invention further contains, if desired, miscible additives such as an additional resin for improving the performance of the resist film, a surfactant for improving the coating property, Dissolution inhibitors, plasticizers, stabilizers, colorants, antihalation agents, dyes, and the like can be appropriately added and contained.

[0094] <Organic solvent (S)>

In the positive resist composition of the present invention, the material is referred to as an organic solvent (hereinafter referred to as “(S) component”). is there. ) And can be produced.

 As the component (S), it is sufficient if each component to be used can be dissolved to form a uniform solution.

One type or two or more types can be appropriately selected and used.

 For example, latones such as γ-butyral rataton; ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl isoamyl ketone, 2_heptanone; Polyethylene alcohol such as diethylene glycol monoacetate, propylene glycol, propylene glycol monoacetate, dipropylene glycol, or dipropylene glycol monoacetate or their monomethyl ether, monoethyl ether, monopropyl ether, monobutyl ether or monophenyl ether And cyclic ethers such as dioxane; methyl lactate, ethyl lactate (EL), methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate And esters such as ethyl, ethyl pyruvate, methyl methoxypropionate and ethyl ethoxypropionate.

 These organic solvents may be used alone or as a mixed solvent of two or more. Further, as the component (S), a mixed solvent obtained by mixing propylene glycol monomethyl ether acetate (PGMEME) and a polar solvent is also preferable. The blending ratio (mass ratio) may be appropriately determined in consideration of the compatibility between PGMEA and the polar solvent, preferably 1: 9 to 9: 1, more preferably 2: 8 to 8: 2. It is preferable to be within the range.

 More specifically, when EL is blended as a polar solvent, the mass ratio of PGMEA: EL is preferably 1: 9 to 9: 1, more preferably 2: 8 to 8: 2.

 In addition, as the component (S), a mixed solvent of at least one selected from PGMEA and EL and γ_petit opening is also preferable. In this case, the mixing ratio of the former and the latter is preferably 70:30 to 95: 5.

 The amount of component (S) used is not particularly limited, but is a concentration that can be applied to a substrate, etc., and is appropriately set according to the coating film thickness. It is used so as to be within a range of 20% by mass, preferably 5 to 15% by mass.

«Resist pattern formation method» The resist pattern forming method of the present invention includes a step of forming a resist film on a substrate using the positive resist composition of the second aspect of the present invention, a step of exposing the resist film, and developing the resist film. More specifically, the method includes a step of forming a resist pattern. More specifically, for example, the resist pattern can be formed by the following resist pattern forming method. That is, first, the resist composition is applied onto a substrate such as a silicon wafer with a spinner or the like, and optionally pre-beta (PAB) is applied to form a resist film. The formed resist film is selectively exposed by, for example, exposure through a mask pattern or drawing by direct irradiation of an electron beam without using a mask pattern, using an exposure apparatus such as an electron beam drawing apparatus or EUV exposure apparatus. After that, apply PEB (post-exposure heating). Subsequently, after developing with an alkali developer, rinsing is performed, and the developer on the substrate and the resist composition dissolved by the developer are washed, poured, and dried to obtain a resist pattern.

 These steps can be performed using a known method. The operating conditions and the like are preferably set as appropriate according to the composition and characteristics of the positive resist composition to be used.

 The exposure light source is not particularly limited. ArF excimer laser, KrF excimer laser, F

 2 Can be performed using radiation such as excimer laser, EUV (extreme ultraviolet), VUV (vacuum ultraviolet), electron beam, X-ray, soft X-ray. In particular, the positive resist composition useful in the present invention is effective for electron beams or EUV, particularly electron beams.

 In some cases, the post-alkali development post-beta step may be included during the above steps.

 In addition, an organic or inorganic antireflection film may be provided between the substrate and the resist film.

Example

 Examples of the present invention will be described below, but the scope of the present invention is not limited to these examples.

Production Example 1: Production of Compound (A) — 1

50 g of polyvalent phenol compound (1) (made by Honshu Chemical Industry) represented by the following formula (1) of 10 g It was dissolved in tetrahydrofuran (THF), and stirred for 10 minutes by adding 60 mass 1 · 12g _^0/0 sodium hydride (NaH) at 0 ° C, represented by the following formula 8. Olg (5) Bromoacetic acid-2-methyl-2-adamantyl was added and stirred at room temperature (rt) for 5 hours. After completion of the reaction, extraction / purification with water / ethyl acetate was performed, and the separated ethyl acetate solution was dried over sodium sulfate and concentrated under reduced pressure to obtain 15.0 g of a compound represented by the following formula (3) (A ) _ l got.

 [Chemical 26]

C5 ′) Compound (A) -1 is analyzed by 1 H-NMR. The results are shown below. From this result, the protection rate per molecule of the compound (A) -1 (ratio of R in the above formula (3) is a group represented by the following formula (5 ′) (mol ⁰ / ₀ )) is 30.2 mol ⁰ /. Met.

— NMR (Heavy dimethyl sulfoxide (DMSO), internal standard: tetramethylsilane) δ = 8. 75- 9. 08 (m 3. 76H), 6. 33— 6. 80 (m 14H), 5. 60— 5 96 (m 2H), 4. 48-4. 75 (m 3. 62H), 3. 41— 3. 63 (m 2H), 1. 35— 2.25 (m 58. 43 H). [0100] Further, Compound (A) -1 was quantified by reversed-phase liquid chromatography under the following conditions, and from the ratio of the peak area, n phenolic hydroxyl groups in the polyvalent phenolic compound (1) ( The ratio of the number of n-protected substances in which n = 0 to 6) was protected was determined. From the ratio of the number of existence, assuming that the compound (A) _1 consists of 1000 molecules, the number of existence of each protector (number) was calculated. The results are shown in Table 1. As shown in Table 1, the compound (A) _1 contained 0 protective strength up to 4 protective strength.

 <Reverse phase liquid chromatography conditions>

 'Device: SERIES1100 manufactured by Hewlett-Packard Company

 'Column: MG type manufactured by Shiseido Co., Ltd. (functional group: C18 particle diameter 3 x m, column inner diameter 4.6 mm, force ram length 75 mm)

 • Detection wavelength: 280nm

 • Flow rate: 2. OmLZ min

 • Measurement temperature: 45 ° C

 • Measurement time: 0-22 minutes

 • Sample injection volume: 1. O / i L

 • Sample concentration (solid content concentration): About 1.3% by mass (diluted with THF)

 • Eluent

 0 ~ :! minutes: (1) pure water / THF = 60/40 (mass ratio)

 1 to 21 minutes: Gradually change from (1) to composition (2) below

 21-22 minutes: (2) pure water / THF = 10/90 (mass ratio).

[0101] [Table 1]

Next, the compound (A) _l was purified by silica gel column chromatography under the following conditions to perform the following operation to obtain a compound (Α) -2.

Purification conditions by silica gel column chromatography: Silica gel (Wacoal gel C100) was used, and ethyl acetate was used as a developing solvent. Silica gel is a substrate (compound ( A) A mass 20 times that of 1) was used. The diameter of the column tube used was 9 cm.

 A sample in which 10 g of Compound (A) -1 was dissolved in a small amount of chloroform was packed in a column, the developing solvent was poured, and the obtained eluate was used as fraction A. The fraction A was dried over sodium sulfate and concentrated under reduced pressure to obtain a compound (A) _2.

[0103] Next, the compound (A) _ 2 was subjected to silica gel column chromatography under the following conditions by carrying out the same operation as described above for the second purification. 5 g was obtained.

 Second purification condition by silica gel column chromatography: Silica gel (Wacoal Gel C200) was used, and Kuroguchi Form: MEK = 9: 1 was used as a developing solvent. The silica gel was used in an amount 20 times the mass of the substrate (compound (A) -2). The column tube diameter used was 9 cm.

 The obtained compound (A) -3 was quantified by reverse-phase liquid chromatography under the above-mentioned conditions, and in the same manner as described above, the number of protections and the protection rate of the protector contained in compound (A) -3 And the number of existence was calculated. The results are shown in Table 2. As shown in Table 2, compound (A) 3 contained only 2 protectors.

[0104] [Table 2]

[0105] Next, proton NMR was measured for the compound (A) -3, and as a result, a mixture of the following two structural isomers (A) 4 and (A) -5 (with a proton NMR ratio (A ) — 4: (A)-5 = 2: 1)

 Next, each structural isomer was separated by column chromatography under the following conditions by performing the following operation, and the structure was assigned.

Purification conditions by column chromatography: Silica Genole (Wacoal Gel C200) was used, and ethyl acetate: hexane = 3: 1 was used as a developing solvent. Silica gel was used in an amount 20 times the mass of the substrate (compound (A) -3). The diameter of the column tube used was 9c m.

 Operation: By performing the same operation as above, 1.5 g of Compound (A) -4 and 0.5 g of Compound (A) -5 were obtained.

· ¹ H-NMR data of compound (A) _4 (heavy DMSO, internal standard: tetramethylsilane): δ

 (ppm) = 9.01 s 2H (— OH (l)), 8.80 s 2H (— OH (4)), 6.28— 6.80 m 14H, 5.70 s 2H (_CH (6)), 4.69 s 4H (_CH (9) ), 3.46 s 2H (

 2

 — CH (11)), 1.25-2.21 m 58H.

 2

 [0107] [Chemical 28]

[0108] · ¹ H-NMR data of compound (A) —5 (heavy DMSO, internal standard: tetramethylsilane): δ

 (ppm) = 8.90 s 1H (—ΟΗ (2)), 8 · 98 s 1H (—OH (3)), 8 · 83 s 2H (—OH (5)), 6.28— 6.80 m 14H, 5.67 s 1H (— CH (7)), 5 · 64 s 1H (— CH (8)), 4.68 s 4H (-CH (10)), 3.52 s 2H (— CH (12)), 1.25— 2.

 twenty two

 21 m 58H.

[0109] [Chemical 29]

 [0110] Examples:! To 3, Comparative Example 1

 Using the compounds (A) _1, (A) _3 to (A) _5 obtained in Production Examples, the components shown in Table 3 below were mixed and dissolved to obtain a positive resist composition solution.

 In Table 3, the numerical value in the mouth indicates the amount (parts by mass). The abbreviations in Table 4 have the following meanings.

 (B) — 1: Triphenylsulfonium nonafluoro-n butanesulfonate (D) — 1: Tri-n-octatinoleamine

 (E) — 1: Salicylic acid

 (S)-1: PGMEA

[0111] Next, the obtained positive resist composition solution was uniformly applied on an 8-inch silicon substrate subjected to hexamethyldisilazane treatment using a spinner, and beta (90 ° C at 110 ° C for 90 seconds. PAB treatment was performed under the PAB) condition to form a resist film (film thickness 150 nm). The resist film is drawn (exposed) with an electron beam drawing machine (HL-800D (VSB) (Hitachi), acceleration voltage 7 OkV), and beta (PEB for 90 seconds at 100 ° C). ) performs a PEB treatment under the conditions, after 2. 200 seconds at 38 weight _^0/0 aqueous solution (23 ° C) developing the tetramethylammonium Niu arm hydroxide (TMAH), 30 seconds rinsing with pure water did. As a result, a 120 nm line and space (LZS) pattern was formed in a 1: 1 ratio.

[0112] The resist pattern obtained was scanned from the top with a scanning electron microscope (SEM) S-9220), and LER was evaluated according to the following criteria. The results are also shown in Table 3.

〇: The line swelled with little power.

 X: The swell of the line was large.

[0113] [Table 3]

As is clear from the above results, the resist pattern obtained using the positive resist composition of Example 13 had less line waviness and reduced LER.

 On the other hand, in Comparative Example 1, LER with a large line undulation was bad.

 Industrial applicability

The present invention can form a resist pattern with reduced roughness, and can be suitably applied to a positive resist composition, a resist pattern forming method, and the positive resist composition.

Claims

The scope of the claims

 The compound represented by the following general formula (I).

Wherein (I), R ¹¹ and R "are each independently 1 to the number of carbon atoms: 10 alkyl group or an aromatic hydrocarbon group, the structure thereof may contain a hetero atom,; R ²¹ ~ R ²⁴ is independently a hydrogen atom or an acid dissociable, dissolution inhibiting group, two of R ^{21 to} R ²⁴ are hydrogen atoms, and the other two are acid dissociable, dissolution inhibiting groups. Yes; j and k are each independently an integer of 0 or 1 and j + k is 4 or less; X is a group represented by the following general formula (la) or (lb) .

[Chemical 2]

 (I a) (I b>

[In the formula (la), R ¹⁸ and R ¹⁹ are each independently an alkyl group having 1 to 10 carbon atoms or an aromatic hydrocarbon group, and may contain a hetero atom in the structure thereof; r, y, z is each independently an integer of 0 or 1 and r + y + z is 4 or less]

The acid dissociable, dissolution inhibiting group is selected from the group consisting of an alkoxycarbonylalkyl group represented by the following general formula (pi) and an alkoxyalkyl group represented by the following general formula (p2). 2. The compound _{c according to} claim 1, which is at least one selected

 [Chemical 3]

 (1) (p 2)

[Wherein R ¹ and R ² are each independently a linear, branched or cyclic alkyl group and may contain a hetero atom in the structure; R ³ is a hydrogen atom or a lower alkyl group; N 'is an integer from:! To 3; ]

 [3] The compound according to claim 1 or 2, which is a compound represented by the following general formula (II):

 [Chemical 4]

[In the formula (II), R ¹¹ and R ^1Z each independently represent an alkyl group having 1 to 10 carbon atoms or an aromatic hydrocarbon group, and may contain a hetero atom in the structure thereof; R ²¹ ˜R ²⁴ is independently a hydrogen atom or an acid dissociable, dissolution inhibiting group, two of R ^{21 to} R ²⁴ are hydrogen atoms, and the other two are acid dissociable, dissolution inhibiting groups. Yes; X is a group represented by the following general formula (la) or (lb). ]

[Chemical 5]

 (I a)

[In the formula (la), R ^1S and R ¹⁹ are each independently an alkyl group having 1 to 10 carbon atoms or an aromatic hydrocarbon group, and may contain a hetero atom in the structure thereof; y and z are each independently an integer of 0 or 1 and r + y + z is 4 or less.]

 A positive resist composition comprising a base component (A) whose alkali solubility is increased by the action of an acid and an acid generator component (B) that generates an acid upon exposure,

 A positive resist composition, wherein the substrate component (A) is a compound (A1) represented by the following general formula (I):

[Chemical 6]

[In the formula (I), R ¹¹ and each independently represents an alkyl group having 1 to 10 carbon atoms or an aromatic hydrocarbon group, and the structure thereof may include a hetero atom; R ^{21 to} R ²⁴ Each independently represents a hydrogen atom or an acid dissociable, dissolution inhibiting group, two of R ^{21 to} R ²⁴ are hydrogen atoms, and the other two are acid dissociable, dissolution inhibiting groups; j and k are each independently an integer of 0 or 1 and j + k is 4 or less; X is a group represented by the following general formula (la) or (lb). Co

[Chemical 7]

:

 《I a》 (1 b)

[In the formula (la), R ^1S and R ¹⁹ are each independently an alkyl group having 1 to 10 carbon atoms or an aromatic hydrocarbon group, and may contain a hetero atom in the structure thereof; y and z are each independently an integer of 0 or 1 and r + y + z is 4 or less.]

 [5] The group consisting of the acid dissociable, dissolution inhibiting group of the compound (A1) consisting of an alkoxycarbonylalkyl group represented by the following general formula (pi) and an alkoxyalkyl group represented by the following general formula (p2) 5. The positive resist composition according to claim 4, wherein the positive resist composition is at least one selected from the group consisting of

 (p 2)

[Wherein R ¹ and R ² are each independently a linear, branched or cyclic alkyl group and may contain a hetero atom in the structure; R ³ is a hydrogen atom or a lower alkyl group; N 'is an integer from:! To 3; ]

 5. The positive resist composition according to claim 4, wherein the compound (Al) is a compound (A1-1) represented by the following general formula (II).

[Chemical 9]

Wherein (II), R ¹¹ and R ¹² are each independently 1 to the number of carbon atoms: 10 alkyl group a or Kaoru aromatic hydrocarbon group, which may contain a hetero atom in the structure thereof; ¹ - ⁴ is independently a hydrogen atom or an acid dissociable, dissolution inhibiting group, two of R ^{21 to} R ²⁴ are hydrogen atoms, and the other two are acid dissociable, dissolution inhibiting groups; X is a group represented by the following general formula (la) or (lb). ]

 [Chemical 10]

 "a" 《Ϊ》

[In the formula (la), R ¹⁸ and R ¹⁹ are each independently an alkyl group having 1 to 10 carbon atoms or an aromatic hydrocarbon group, and may contain a hetero atom in the structure thereof; y and z are each independently an integer of 0 or 1 and r + y + z is 4 or less.]

[7] The positive resist composition according to any one of [4] to [6], further comprising a nitrogen-containing organic compound (D).

 [8] A step of forming a resist film on a substrate using the positive resist composition according to any one of claims 4 to 6, a step of exposing the resist film, and developing the resist film. A resist pattern forming method including a step of forming a resist pattern.